Rectifier circuit



E. w. LINCOLN 1,724,607

RECTIFIER CIRCUITS Aug. 13, 1929.

Filed` May 9,4v 1927 l04 J3 l) E Lwlumhaf www@ /5 "1 V V V V A13 i Een 16 v Y. 2a Emma 27 L-annum I Foo 1K, gw 30 1l 19 MH, gg

Y Patented Aug. 13, 6.19279.

UNITED STATI-:s

`PirrisNr OFFICE.

I ELMER W. LINCOLN, OF CHICAGO, ILLINOIS, ASSIGNOR TO FANSTEEL PRODUCTS CCNL' PANY, ING., 0F CHICAGO, ILLINOIS, A CORPORATION OF NEW YORK.

REOTIFIER CIRCUIT.

Application led May 9, 1927. Serial 11o. 189,858.

This invention relates to circuits wherein alternating current is rectified to yield a direct pulsating current and the pulsating current is then smoothed out by means of a filter system. I y

The Object of this invention is to enable alternating current1 to be used for telephone and radio work without causing a hum 1n .the phones.`

A further object of this invention is to smooth out pulsations in such a current by the use of two wlindingson a single inductance core. .f f.

Other objects will beapparentas the de- 15 tailed description ofvmy invention proceeds.

In the accompanying drawings, which represent preferred embodiments of my invention, i

Fig. 1 is a -diagrammatic illustration of an embodiment using a unidirectional condenser `bridge between positive and negative conductors, and 1 l v Fig. 2 is a similar drawing in which the condenser is replaced by a smaller condenser in series with a parallel arrangement of inductance and capacity.

' Alternating current .is supplied from a source-lwhich ma be an ordinary 110 volt 'lighting circuit. lts voltage lis stepped downby transformer 11 which comprises a primary'coil 12 and a secondary coil 13 wound on a core 14. One terminal of the secondary 13 is connected to the lead terminal of an electrolytic rectifier 16 by a conductor 15. vThis rectifier is preferablv Aof the type disclosed in the patent tov E. IV. Engle, No. 1,495,582, dated May 27, 1924, Re. October 12, 1926, as No. 16,438, and consists of a tantaluin electrode and a lead electrode immersed in a sulphuricacid electrolyte to which has been added a small amount 4 ofasalt of a metal of the iron group.

The tantalum electrode of rectifier 16 is connected by conductor 17 to a winding 18 on a choke ring 1 9. The choke ring is' preferably a laminated iron core with a cross section area of about 1/2 square inch, and the winding in the preferred embodiment consists of 225 turns of No. 21 wire. The other terminal of the winding is connected by a conductor 20 to the positive terminal of a.

lead storage battery 21. This terminal also has a conductor 22'leading to a. load which may be a radio 'receiving set, a telephone switchboard, etc. The negative terminal of vsecondary winding. clockwise in the circuit, the tantalum electhe storage battery-21 is connected by a conductor 23 to the loadand-by a conductor 24 to a choke coil 2,5 woundaround the other side of the laminated choke ring 19 The windings 18 and 25 arein such a direction thatthe electromagnetic lines are in the same direction; i. e., the effect of the windings is additive and they do not neutralize each other,` The other 'terminal of the winding 25 is connected by a conductor 26 4to the lead terminal of rectifier'27, the tantalum electrode of this rectifier being connected b v a.' conductor 28 to the terminal of the secondary coil 13, referred to above.

'Bridged across conductors 17 and-26 there is a'unidirectional condenser 29 .which is preferably'of the electrolytic type.

In my preferred embodiment, I use a tantalumelead-sulphuric acid cell inv which vthe area of the tantalum is aboutv 66 square inches. The tantalum is connected to conductor 17 and the lead to conductor 26, as shown in Fig. 1. The other end of the secondary l13 -is 4connected by conductor 30 to the center of storage battery 21.

The modification shown in Fig. 2 is the same as that described above with the exception that the unidirectional condenser 29 is replaced by paper condensers 3.1 and 32, an inductance 33 being bridged across condenser 32, as shown in the drawing. `The Object of this change is to reduce the required capacity of the condensers, and with this arrangement` condensenSl may have a .capacity of 15 microfarads andv condenser 32 a capacity of 2 microfaiads.

The operation of my invention may bedescribed as follows:

.When current is flowing counter-clockwise in the secondary circuit, the tantalum electrodeof cell 27 will act as a closed valve and current will How through 15, 16, 17, 18

and 20, the left half of the storage battery 21 and through 3() to the other side of the `When current Hows trode in cell 16 acts as a closed valve and current flows .through30, the right half 'of lead storage battery 21 and conductors 24,

` 25, 26, 27 and 28 'to the opposite side of the secondaryv winding 13.l Thus the current through 15, 17 and 20 is always owin to the load and it may, therefore, be terme the y positive side or conductor. The conductors 24, 26 and 28 permit current to flow only towardthe source and for this reason they may be termed negative conductors, the terms positive and negative indicating whether the current is fiowing toward the load or toward the source.

, It vwill be noted that the left half ofthe storage battery is chargedby one wave and the right half by the other wave of the rectified current. This feature tends to eliminate the pulsating effect in conduct-ors 22 and 23. The use of the choke ring 19,.pro vided with windings 1S and 25, serves to furtherreduce the pulsations and also to increase the charging rate.

' I have found that the choke ring must be wound, as shownin the drawings, to give thedesired charging rate, and that if the opposite windings are used or separate inductances are employed, thev charging rate is materially lowered and the same filtering action is not obtained. The construction of the choke coil, which has two windings on a ring type core, is somewhat like a transformer, due to the fact that the charger is of the double half wave type, so that the current and voltage builds upin one winding during one charging 1period, which is half of a cycle, and -then ti winding, which is the other half of the cycle. Then the voltage is built up by the charging 'rate passing through the choke coil, a counter voltage is built' up in the other winding which tends to add to the voltage of the battery, and thereby gives additional voltage impressed upon the tantalum condenser, which gives a higher charge. This condition is repeated every half cycle in which case the voltage is added to the battery voltage and increases the impressed voltage upon "the tantalum condenser. This -condition is very evident inthis type of action, as when two separate coils are used, which have complete ring type chokes, the filtering effect cannot b e compared with the effect gained' by the choke being constructed of one coil with the two windings.

Vhile I'have described'in detail a pre- ,Y

4ferred embodiment'of my invention, it is understood that I do not limit myselffto 'any particular theory of operation or to the specific details shown except as defined by the following claims. f j

What I claim is:4

v' l. A rectifier circuitincluding rectfyin'g'vr means, a storage battery, connections berough the other tween said rectifier means and said storage battery whereby it is charged inl sections, a

choke ring,- windings in both conductors on v said choke ring-to produce an additiveeffect,

and a condens-er bridged across said conduc-v additive windings, a storage battery and con` nections from one end of the secondary winding to the lead terminal of the vfirst rectifier,

from the tantalum terminal of this rectifier to the condenser andi to a winding on the choke ring, from this choke winding to the positive side of the battery and to a load, from the load andthe negative side of the battery to the second vWindingv on the chokering, from the second choke Winding to the other terminal ofthe condenser and to the lead` plate of the second rectifier, from the tantalum plate of this rectifier to the same A terminal of the secondary winding, and from the other terminal of the secondary winding tothe center of the storage battery.

3. In a circuit wherein two rectifiers are ter'nating current and to charge aA storage battery'in sections, a choke ring, a conductor from each rectifier wound about said choke connected to use both half -wavesof an alj y ring to produce a magnetic field in the same direction, and a capacity unit bridged across the conductors between the rectiers andthe chokey ring.

4. A, rectifying circuit comprising a transformer secondary, a storage battery, a connection between one terminal of the second-K Y ary and the center ofthe storage battery,

two single half-wave rectifiers, connections between unlike electrodes of said rectifiers and -the other terminal of the transformer secondary, positive and lnegative conductors connecting the other, rectierl electrodes' withl the positive and negative terminals of the storage battery, a choke ring, Windin'gsin saidpositive and negative conductors on said ring to produce ux'in'the' same direction, anda capacity device bridging said positive land negative conductors between said rings and said rectifers. l

In Witnesswhereof, I hereunto subscribe v my name this 6th day of April, 1927. g i ELMER.W. LINCOLN. 

